One assumes the greenhouse collectors can also be used for food production - if so, this becomes more space efficient than PV by a long way, potentially.
Probably not. Plants have a relatively small "sweet spot", and greenhouses try quite hard to prevent overheating. The glass panes can be raised to let hot air escape, and they'll even have blinds.
25C (77F) is about ideal, with 20-30C (68-86F) being somewhat acceptable before seeing a huge reduction in crop yield. Higher temperatures will also significantly increase water consumption.
Temperature in a solar updraft tower is about 20-30C above ambient. That pretty much immediately rules out dual use in all but the coldest environments.
Thanks for the reply! I was thinking that the greenhouses would be arranged in a circle, so there'd be a sweet spot in a ring at the very least. But it does sound rather.. difficult. I suppose that sweet spot would also not be in a fixed place, either. Pity.
